Tolkien (crater)

Tolkien
	MESSENGER image with Tolkien at center. The north pole is on the rim of Tryggvadóttir, the crater at left foreground.
Planet	Mercury
Coordinates	88°49′N211°05′W / 88.82°N 211.08°W Coordinates: 88°49′N211°05′W / 88.82°N 211.08°W
Quadrangle	Borealis
Diameter	50 km
Eponym	J. R. R. Tolkien

Last updated January 25, 2023

Processed image of the northernmost part of planet Mercury: this shows the temperatures at the North Polar Region, which ranges from >400 K (red) to 50 K (purple). Tolkien is on the left of the image. PIA19247-Mercury-NPolarRegion-Messenger20150316.jpg — Processed image of the northernmost part of planet Mercury: this shows the temperatures at the North Polar Region, which ranges from >400 K (red) to 50 K (purple). Tolkien is on the left of the image.

Tolkien is one of the northernmost craters on Mercury, located in the Borealis quadrangle (north pole region) at 88.82 N, 211.08 W.^[1] It is 50 km in diameter. It was named after the South African born British writer J. R. R. Tolkien. The name was approved by IAU's Working Group for Planetary System Nomenclature on August 6, 2012.^[1] Since Tolkien is very close to the north pole, and Mercury has almost no axial tilt, Tolkien receives very little sunlight.^[2] S band radar data from the Arecibo Observatory collected between 1999 and 2005 indicates a radar-bright area covers the entire floor of Tolkien, which is probably indicative of a water ice deposit.^[3]^[4]^[5]^[6]

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The geology of Mercury is the scientific study of the surface, crust, and interior of the planet Mercury. It emphasizes the composition, structure, history, and physical processes that shape the planet. It is analogous to the field of terrestrial geology. In planetary science, the term geology is used in its broadest sense to mean the study of the solid parts of planets and moons. The term incorporates aspects of geophysics, geochemistry, mineralogy, geodesy, and cartography.

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Vonnegut is a crater on Mercury, near the north pole. It was named by the IAU in 2017 after the American author Kurt Vonnegut. Part of Vonnegut's 1959 novel The Sirens of Titan takes place on Mercury. The crater was referred to as e5 in scientific literature prior to naming.

Yoshikawa is a crater on Mercury, near the north pole. It was named by the IAU in 2012 after the Japanese novelist Eiji Yoshikawa.

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Laxness is a crater on Mercury, located near the north pole. It was named by the IAU in 2013, after Icelandic writer Halldór Laxness.

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Tryggvadóttir is a crater on Mercury. The north pole of Mercury is located next to its northern rim. It was named by the IAU in 2012 after the Icelandic artist Nína Tryggvadóttir.

Chesterton is a crater on Mercury, near the north pole. Its name was adopted by the International Astronomical Union in 2012, after the English author G. K. Chesterton.

Rustaveli is a crater on Mercury. Its name was adopted by the International Astronomical Union in 2012, after the Georgian poet Shota Rustaveli.

Gordimer is a crater on Mercury, near the north pole. Its name was adopted by the International Astronomical Union (IAU) in 2019, after the South African writer Nadine Gordimer.

L'Engle is a crater on Mercury, located near the south pole. Its name was adopted by the International Astronomical Union (IAU) in 2013, after American author Madeleine L'Engle.

Lovecraft is a crater on Mercury, located near the south pole. Its name was adopted by the International Astronomical Union (IAU) in 2013, after American author Howard Phillips Lovecraft.

Hurley is a crater on Mercury, located near the south pole. Its name was adopted by the International Astronomical Union (IAU) in 2013, after Australian photographer Frank Hurley.

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References

1 2 "Tolkien (crater)". Gazetteer of Planetary Nomenclature. USGS Astrogeology Research Program., accessed 19 February 2019
↑ "Permanently Shaded Polar Craters". NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington/National Astronomy and Ionosphere Center, Arecibo Observatory. 15 November 2012.
↑ Chabot, N. L., D. J. Lawrence, G. A. Neumann, W. C. Feldman, and D. A. Paige, 2018. Mercury's Polar Deposits. In Mercury: The View After MESSENGER edited by Sean C. Solomon, Larry R. Nittler, and Brian J. Anderson. Cambridge Planetary Science. Chapter 13, Figure 13.2.
↑ NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington (16 March 2015). "Hot and Cold".
↑ PIA19411: Water Ice on Mercury, NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington
↑ John K. Harmon, Martin A. Slade, Melissa S. Rice, 2011. Radar imagery of Mercury’s putative polar ice: 1999–2005 Arecibo results. Icarus, 211, p37-50. doi.org/10.1016/j.icarus.2010.08.007

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[gpn-1] 1 2 "Tolkien (crater)". Gazetteer of Planetary Nomenclature. USGS Astrogeology Research Program., accessed 19 February 2019

[2] "Permanently Shaded Polar Craters". NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington/National Astronomy and Ionosphere Center, Arecibo Observatory. 15 November 2012.

[3] Chabot, N. L., D. J. Lawrence, G. A. Neumann, W. C. Feldman, and D. A. Paige, 2018. Mercury's Polar Deposits. In Mercury: The View After MESSENGER edited by Sean C. Solomon, Larry R. Nittler, and Brian J. Anderson. Cambridge Planetary Science. Chapter 13, Figure 13.2.

[4] NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington (16 March 2015). "Hot and Cold".

[5] PIA19411: Water Ice on Mercury, NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington

[6] John K. Harmon, Martin A. Slade, Melissa S. Rice, 2011. Radar imagery of Mercury’s putative polar ice: 1999–2005 Arecibo results. Icarus, 211, p37-50. doi.org/10.1016/j.icarus.2010.08.007

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Tolkien (crater)

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References

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